I'm wanting to get my 6MT tranny fluid drained and filled. Wanting to hear everyone's thoughts if you've had this done and if you went with the OEM BMW 75w80 fluid or went with something else like Redline MTL.

Noting that before Long Life fluids were introduced, BMW appear to have recommended changing the fluid every couple of years, your car which is filled with Long Life fluid - is unlikely to need a change for some time.

Obviously, if you believe the "Lifetime Fill" message, it will end up being a self-fulfilling prophecy, but you still shouldn't need to touch it for several years.

I'm sticking to BMW stuff on the M2, but I used Redline and SyncroMax on my Mustang before.

Both were better for high temp use, but struggled at low temps in the cold months. In the end I went back to what Ford recommended and that worked well enough on track (though it had that mushy feeling on track) but was baby smooth on the street and at low temps.

I'm sticking to BMW stuff on the M2, but I used Redline and SyncroMax on my Mustang before.

Both were better for high temp use, but struggled at low temps in the cold months. In the end I went back to what Ford recommended and that worked well enough on track (though it had that mushy feeling on track) but was baby smooth on the street and at low temps.

Awesome! I was thinking of going with the BMW fluid too. There must be a reason when their fluid is so much more costly vs the redline.

Might be overkill but personally I'll drain and fill my tranny every 30-50k miles

Awesome! I was thinking of going with the BMW fluid too. There must be a reason when their fluid is so much more costly vs the redline.

Might be overkill but personally I'll drain and fill my tranny every 30-50k miles

My prior 335i was a 6MT and yes I did change the fluid (so easy) and while researching the OEM fluid (way more expensive) I came up with these thoughts:

1. OEM Fluid is way more expensive than Redline Fluid
2. Redline Fluid was recommended by Mike Miller & Bimmerworld
3. Most users of the Redline Fluid (MTL & MT-90) Found Smooth Operation
4. BMW OEM is made to last Lifetime (say 100k miles)
5. Redline Tranny Oil is recommended to be changed (say 30K miles)

I was afraid to move away from OEM and paid big bucks for the OEM Fluid at 50K miles but then at 100K I changed to Redline (I mixed MTL with MT-90) and along with the Clutch Delay Valve delete -- I was amazed how smooth the gears shifted (BMW tech even commented how good the gears shifted).

Awesome! I was thinking of going with the BMW fluid too. There must be a reason when their fluid is so much more costly vs the redline.

Might be overkill but personally I'll drain and fill my tranny every 30-50k miles

My prior 335i was a 6MT and yes I did change the fluid (so easy) and while researching the OEM fluid (way more expensive) I came up with these thoughts:

1. OEM Fluid is way more expensive than Redline Fluid
2. Redline Fluid was recommended by Mike Miller & Bimmerworld
3. Most users of the Redline Fluid (MTL & MT-90) Found Smooth Operation
4. BMW OEM is made to last Lifetime (say 100k miles)
5. Redline Tranny Oil is recommended to be changed (say 30K miles)

I was afraid to move away from OEM and paid big bucks for the OEM Fluid at 50K miles but then at 100K I changed to Redline (I mixed MTL with MT-90) and along with the Clutch Delay Valve delete -- I was amazed how smooth the gears shifted (BMW tech even commented how good the gears shifted).

Thank for this insight. I completely forgot about Mike Miller's guide and you're correct. He does recommend redline MTL! Sounds like that's what I will try. Recently my tranny has been a bit more notchy than it used to be. I'm at roughly 20k miles

Hmm... unlikely to be the stock fluid breaking down, but looking forward to hearing how you get on.

I'm attributing it to gunk and flakes in the oil rather than the oil itself going bad. My hypothesis is that since the fluid wasn't changed during break in there's a lot of stuff floating around in it.

For sure I know the diff has a bunch of crap in it at the 1200 mile drain and fill. I'll update this thread if I remember to after I do the tranny fluid change

I'm attributing it to gunk and flakes in the oil rather than the oil itself going bad. My hypothesis is that since the fluid wasn't changed during break in there's a lot of stuff floating around in it.

For sure I know the diff has a bunch of crap in it at the 1200 mile drain and fill. I'll update this thread if I remember to after I do the tranny fluid change

Looking forward to your update (if you remember to ). I'm wondering if a diff+transmission fluid flush would improve the gear changes, not that it's bad right now. But there are days where it's incredibly notchy/crunchy.